Fractal modelling of medium–high porosity SiC ceramics

A fractal model (denominated IFU) is presented, developed by varying some constructive aspects of Menger sponge. Simple fractals can be used effectively to describe pore size distributions which present a regular growth toward the larger diameters and therefore are not suited to the description of very common structures which present one or more peaks in the distribution. The use of more fractal units means that the IFU is able to simulate effectively the pore size distribution, the volume fractions of the voids and the geometry of the microstructure. The modelling is applied to sets of published data regarding SiC based ceramics characterised by a medium–high volume fraction (40%/80%), obtained through the technique of mercury intrusion porosimetry. Finally, this study demonstrates how the permeability can be realistically estimated based on the parameters of the proposed model.